Plasticizing device and three-dimensional shaping device

ABSTRACT

A plasticizing device includes: a drive motor; a rotating unit driven to rotate about a rotation axis by the drive motor and having an end surface perpendicular to the rotation axis and a lateral surface intersecting with the end surface; a barrel having a bottom surface facing the end surface of the rotating unit, and a heater; a case accommodating the rotating unit; and a material supply unit accommodating the material. At least one of the barrel and the case has a sidewall surface facing the lateral surface of the rotating unit and standing up along an outer circumference of the bottom surface of the barrel. At the bottom surface of the barrel, a communication hole through which the molten material flows out and a spiral groove part coupled to the communication hole are formed. The lateral surface of the rotating unit and the sidewall surface together define a supply space where the material is supplied from the material supply unit to the groove part.

The present application is based on, and claims priority from, JPApplication Serial Number 2018-178937, filed Sep. 25, 2018, thedisclosure of which is hereby incorporated by reference herein in itsentirety.

BACKGROUND 1. Technical Field

The present disclosure relates to a plasticizing device and athree-dimensional shaping device.

2. Related Art

For example, JP-A-2010-241016 discloses a plasticizing device which hasa rotor having a helical groove formed at an end surface, and a barrelfacing the end surface of the rotor where the helical groove is formedand having a communication hole at the center. In this plasticizingdevice, a material is supplied into the helical groove of the rotor froma hopper at a timing when a material outlet port of the hopper and amaterial inlet port provided at a lateral side of the rotating rotoroverlap each other.

In the above plasticizing device, the material is supplied into thehelical groove of the rotor from the hopper according to the rotationcycle of the rotor. Therefore, during the period from a timing when thematerial is supplied into the spiral groove of the rotor from the hopperto the next timing when the material is supplied, the material melted inthe spiral groove flows out from the communication hole of the barreland the amount of the material in the spiral groove decreases. Thus, theapplicant of the present disclosure has found that the pressure of themolten material pressure-fed into the communication hole changes,causing a change in the flow rate of the molten material ejected fromthe communication hole.

SUMMARY

The present disclosure proposes a plasticizing device in which thechange in the flow rate of the molten material ejected from thecommunication hole is small.

According to an aspect of the present disclosure, a plasticizing deviceplasticizing a material into a molten material is provided. Theplasticizing device includes: a drive motor; a rotating unit driven torotate about a rotation axis by the drive motor and having an endsurface perpendicular to the rotation axis and a lateral surfaceintersecting with the end surface; a barrel having a bottom surfacefacing the end surface of the rotating unit, and a heater; a caseaccommodating the rotating unit; and a material supply unitaccommodating the material. At least one of the barrel and the case hasa sidewall surface facing the lateral surface of the rotating unit andstanding up along an outer circumference of the bottom surface of thebarrel. At the bottom surface of the barrel, a communication holethrough which the molten material flows out and a spiral groove partcoupled to the communication hole are formed. The lateral surface of therotating unit and the sidewall surface together define a supply spacewhere the material is supplied from the material supply unit to thegroove part.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an explanatory view showing a schematic configuration of athree-dimensional shaping device in a first embodiment.

FIG. 2 is a perspective view showing a configuration of a flat screw inthe first embodiment.

FIG. 3 is a top view showing a configuration of a bottom surface of abarrel in the first embodiment.

FIG. 4 is an explanatory view showing a schematic configuration of athree-dimensional shaping device in a second embodiment.

FIG. 5 is a top view showing a configuration of a bottom surface of abarrel in the second embodiment.

FIG. 6 is a cross-sectional view taken along VI-VI of the barrel in thesecond embodiment.

FIG. 7 is a top view showing a configuration of a bottom surface of abarrel in a third embodiment.

FIG. 8 is an explanatory view showing a schematic configuration of aninjection molding device in another form.

DESCRIPTION OF EXEMPLARY EMBODIMENTS A. First Embodiment

FIG. 1 is an explanatory view showing a schematic configuration of athree-dimensional shaping device 100 in a first embodiment. In FIG. 1,arrows along X, Y, and Z-axes orthogonal to each other are shown. TheX-axis and the Y-axis are along the horizontal direction. The Z-axis isalong the vertical direction. Similarly, arrows along the X, Y, andZ-axes are shown in the other drawings, according to need. The X, Y, andZ-axes in FIG. 1 represent the same axes as the X, Y, and Z-axes in theother drawings.

The three-dimensional shaping device 100 has: an ejection unit 200including a nozzle unit 60, a flow rate adjustment mechanism 70, and aplasticizing device 90; a shaping table 310; a movement mechanism 320;and a control unit 500. In the three-dimensional shaping device 100 inthis embodiment, under the control of the control unit 500, a shapingmaterial plasticized by the plasticizing device 90 is supplied to thenozzle unit 60, and the shaping material ejected from a nozzle hole 61of the nozzle unit 60 is stacked at the top of the shaping table 310,thus shaping a three-dimensional shaped object. The shaping material maybe referred to as a molten material.

The movement mechanism 320 changes the relative position between theshaping table 310 and the ejection unit 200. In this embodiment, themovement mechanism. 320 moves the shaping table 310 relative to theejection unit 200. The movement mechanism 320 in this embodiment isformed of a three-axis positioner which moves the shaping table 310along the three axes of X, Y, and Z by drive forces of three motors.Each motor drives under the control of the control unit 500.

Instead of being configured to move the shaping table 310, the movementmechanism 320 may be configured to move the ejection unit 200 withoutmoving the shaping table 310. The movement mechanism. 320 may also beconfigured to move both the shaping table 310 and the ejection unit 200.The movement mechanism 320 may have any configuration that can changethe relative position between the shaping table 310 and the ejectionunit 200.

The control unit 500 is formed of a computer having one or moreprocessors, a main storage device, and an input/output interface toinput a signal from outside and output a signal to outside. In thisembodiment, the control unit 500 causes the processor to execute aprogram or command read into the main storage device and therebycontrols an operation of the ejection unit 200 and the movementmechanism 320, thus executing shaping processing to shape athree-dimensional shaped object. The operation includes a movement ofthe three-dimensional relative position of the ejection unit 200relative to the shaping table 310. The control unit 500 may also beconfigured of a combination of a plurality of circuits, instead of acomputer.

The plasticizing device 90 has a material supply unit 20 and aplasticizing unit 30. The material supply unit 20 and the plasticizingunit 30 communicate with each other via a supply path 22. Theplasticizing unit 30 and the nozzle hole 61 of the nozzle unit 60communicate with each other via a communication hole 55. Theplasticizing device 90 at least partly melts a solid-state material andsupplies the resulting paste-like shaping material to the nozzle unit60.

The material supply unit 20 accommodates a material in the state ofpellets, powder or the like. The material in this embodiment is ABSresin in the form of pellets. The material supply unit 20 in thisembodiment is formed of a hopper. The material accommodated in thematerial supply unit 20 is supplied to the plasticizing unit 30 via thesupply path 22 provided below the material supply unit 20.

The plasticizing unit 30 has a screw case 31, a drive motor 32, a flatscrew 40, and a barrel 50. The screw case 31 is a casing accommodatingthe flat screw 40. The drive motor 32 is fixed to a top surface of thescrew case 31. The drive motor 32 drives under the control of thecontrol unit 500 and thus rotates the flat screw 40 about a rotationaxis RX. The flat screw 40 maybe referred to as a rotating unit. Thescrew case 31 may be simply referred to as a case.

In this embodiment, the flat screw 40 is arranged in the screw case 31in such a way that the rotation axis RX is parallel to the Z-axis. Thedrive motor 32 is coupled to a top surface of flat screw 40. A torquegenerated by the drive motor 32 causes the flat screw 40 to rotate aboutthe rotation axis RX in the screw case 31. The flat screw 40 has an endsurface 45 perpendicular to the rotation axis RX, at the side oppositeto the surface where the drive motor 32 is coupled. The flat screw 40has a lateral surface 46 intersecting with the end surface 45. Thedetailed shape of the flat screw 40 will be described later withreference to FIG. 2.

In this embodiment, the barrel 50 is fixed to the bottom side of thescrew case 31. The barrel 50 has a bottom surface 51 facing the endsurface 45 of the flat screw 40. In the bottom surface 51, thecommunication hole 55 is provided at a position on the rotation axis RXof the flat screw 40. A spiral groove part 56 is provided around thecommunication hole 55 in the bottom surface 51. The barrel 50 has abuilt-in heater 58. The temperature of the heater 58 is controlled bythe control unit 500. The detailed shape of the barrel 50 will bedescribed later with reference to FIG. 3.

In this embodiment, the barrel 50 and the screw case 31 together form asidewall surface 52 facing the lateral surface 46 of the flat screw 40and standing up along the outer circumference of the bottom surface 51.In this embodiment, an upper-side part of the sidewall surface 52 isformed by an inner wall surface of the screw case 31. A supply port 25communicating with the material supply unit 20 is provided at the innerwall surface of the screw case 31. A lower-side part of the sidewallsurface 52 is formed by a wall surface standing up from the bottomsurface 51 of the barrel 50. Also, the sidewall surface 52 may be formedby the screw case 31 alone, where the inner wall surface of the screwcase 31 extends to the bottom surface 51 of the barrel 50. The sidewallsurface 52 may also be formed by the barrel 50 alone, where the wallsurface standing up from the bottom surface of the barrel 50 extends toabove the top surface of the flat screw 40.

In this embodiment, the wall surface of the barrel 50 forming thesidewall surface 52 has a slope part 53 at a position intersecting withthe bottom surface 51. The slope part 53 is sloped in such a way as toapproach the center of the bottom surface 51 as it goes toward thebottom surface 51.

The lateral surface 46 of the flat screw 40 and the sidewall surface 52together define a supply space 59 where the material is supplied fromthe material supply unit 20 to the groove part 56. The supply space 59is a space where the material can circulate from the supply port 25 intothe groove part 56.

The flow rate adjustment mechanism 70 is provided with a valve mechanism71. The valve mechanism 71 in this embodiment is formed of a butterflyvalve. The valve mechanism 71 opens and closes under the control of thecontrol unit 500 and switches between communication andnon-communication between the communication hole 55 and the nozzle hole61.

Inside the nozzle unit 60, a nozzle flow path 62 and the nozzle hole 61are provided. The nozzle hole 61 is a part that is provided at an endpart at the side communicating with the atmosphere and that has areduced flow path cross section, in the nozzle unit 60. The nozzle flowpath 62 is supplied with the shaping material from the plasticizingdevice 90 via the flow rate adjustment mechanism 70. The shapingmaterial supplied to the nozzle flow path 62 is ejected from the nozzlehole 61. In this embodiment, the diameter of the nozzle flow path 62 isthe same as the diameter of the communication hole 55. However, thediameter of the nozzle flow path 62 may be smaller than the diameter ofthe communication hole 55. A nozzle diameter Dn of the nozzle hole 61 issmaller than the diameter of the nozzle flow path 62. The nozzlediameter Dn is the diameter of the nozzle hole 61 at the end part at theside communicating with the atmosphere.

FIG. 2 is a perspective view showing the configuration of the flat screw40 in the first embodiment. The flat screw 40 shown in FIG. 2 is in thestate where the up-down positional relation shown in FIG. 1 is reversedin order to facilitate understanding of the technology. The flat screw40 in this embodiment has a main body part 41, a flange part 42, and aplurality of blade parts 43. In the flat screw 40 in this embodiment,the main body part 41, the flange part 42, and the plurality of bladeparts 43 are molded as one body.

The main body part 41 is substantially cylindrical. The main body part41 has the foregoing end surface 45. The diameter of the main body part41 near the end surface 45 becomes smaller as it goes toward the endsurface 45.

The flange part 42 is a disk-like part provided at the side opposite tothe end surface 45 in the axial direction of the main body part 41. Theradius of the flange part 42 is larger than the radius of the main bodypart 41.

The blade part 43 is a part protruding in a radial direction of the mainbody part 41 from the lateral surface 46 of the main body part 41. Theblade part 43 is provided between the end surface 45 and the flange part42 in the axial direction of the main body part 41. The blade part 43 iscoupled to the lateral surface 46 of the main body part 41 and to theflange part 42. A part at the side of the end surface 45, of the bladepart 43, is sloped so as not to interfere with the slope part 53 of thebarrel 50. In this embodiment, eight blade parts 43 are arranged atequal intervals in the circumferential direction of the main body part41.

FIG. 3 is a top view showing the configuration of the bottom surface 51of the barrel 50 in the first embodiment. As described above, thecommunication hole 55 and the spiral groove part 56 are formed at thebottom surface 51 of the barrel 50. In FIG. 3, the groove part 56 ishatched in order to facilitate understanding of the technology.

The communication hole 55 is provided at the center of the bottomsurface 51. The groove part 56 has a center part 151, a spiral part 152,and a material inflow part 153. The center part 151 is a circulardepression around the communication hole 55. One end of the spiral part152 is coupled to the communication hole 55 via the center part 151. Thespiral part 152 spirally extends about the center part 151 in such a wayas to form an arc toward the outer circumference of the bottom surface51. The spiral part 152 may be formed in such a way as to extend in theshape of an involute curve or helically.

In this embodiment, the cross section of the spiral part 152perpendicular to the direction of a tangent to the spiral isrectangular. The cross-sectional area of the spiral part 152 in thisembodiment is constant. In this embodiment, since the cross section ofthe spiral part 152 is rectangular, the cross-sectional area of thespiral part 152 can be calculated as the product of the width and depthof the groove of the spiral part 152. Also, the cross section of thespiral part 152 maybe other than rectangular. For example, the crosssection of the spiral part 152 may be semicircular. In this case, thecross-sectional area of the spiral part 152 can be calculated using pi(the ratio of the circumference of the circle to its diameter) and theradius of the groove of the spiral part 152.

The other end of the spiral part 152 is coupled to the material inflowpart 153. The material inflow part 153 is a groove-like part provided atthe outer circumferential edge of the bottom surface 51 and wider thanthe spiral part 152. The supply port 25 of the supply path 22 isarranged above the material inflow part 153.

In the above configuration of the three-dimensional shaping device 100,as the control unit 500 executes shaping processing to shape athree-dimensional shaped object, the material in the material supplyunit 20 travels through the supply port 25 and is supplied into thesupply space 59 between the lateral surface 46 of the rotating flatscrew 40 and the sidewall surface 52 formed by the screw case 31 and thebarrel 50.

In this embodiment, the blade part 43 of the rotating flat screw 40circles inside the supply space 59. Therefore, the material suppliedfrom the supply port 25 sequentially fills the space between therespective blade parts 43 of the rotating flat screw 40. A part of thematerial filling the space between the blade parts 43 is supplied intothe material inflow part 153 at a timing when this space overlaps thematerial inflow part 153. In the space between the blade parts 43 wherethe amount of the material filling the space is reduced as the materialis supplied into the material inflow part 153, the material isadditionally supplied from the supply port 25 at a timing when thisspace overlaps the supply port 25. Therefore, the inside of the supplyspace 59 is filled with the material while the flat screw 40 isrotating.

The material supplied into the material inflow part 153 is transportedinto the spiral part 152 by the rotation of the flat screw 40. Thematerial transported into the spiral part 152 is at least partly meltedby the rotation of the flat screw 40 and the heating by the heater 58built inside the barrel 50, and thus becomes a fluid paste-like shapingmaterial. The shaping material is transported within the spiral part 152and pressure-fed into the communication hole 55 by the rotation of theflat screw 40. The shaping material supplied to the nozzle unit 60 viathe communication hole 55 is ejected from the nozzle hole 61 toward thetop of the shaping table 310.

In the three-dimensional shaping device 100 in this embodiment describedabove, the material supplied from the material supply unit 20 is storedin the supply space 59 provided between the flat screw 40 and the barrel50. This enables continuous supply of the material from the supply space59 to the groove part 56. Therefore, a change in the pressure of theshaping material pressure-fed into the communication hole 55 can berestrained and a change in the flow rate of the shaping material ejectedfrom the communication hole 55 can be restrained. Thus, a change in theflow rate of the shaping material ejected from the nozzle hole 61 can berestrained.

Also, in this embodiment, the blade part 43 protruding in the radialdirection of the rotating flat screw 40 can stir the material inside thesupply space 59. Therefore, the material can be restrained from adheringto the barrel 50 and closing the supply space 59.

Also, in this embodiment, the material supplied from the supply port 25provided above the slope part 53 flows along the slope part 53 andsmoothly flows into the material inflow part 153. This facilitates thesupply of the material into the material inflow part 153.

In this embodiment, ABS resin pellets are used as the material. However,as the material used in the ejection unit 200, a material shaping athree-dimensional shaped object which contains various materials such asthermoplastic material, metal material, and ceramic material, as itsmain material, can be employed. Here, the “main material” means amaterial mainly contributing to the shaping of the three-dimensionalshaped object and means a material whose content in thethree-dimensional shaped object is 50% by weight or higher. The shapingmaterial includes the main material melted as a single material, or apaste-like material in which a part of a component contained along withthe main material is melted.

When a thermoplastic material is used as the main material, theplasticizing device 90 plasticizes the material and thus produces theshaping material. The term “plasticize” means to melt the thermoplasticmaterial by applying heat.

As the thermoplastic material, for example, one or a combination of twoor more of the following thermoplastic materials can be used.

Examples of Thermoplastic Material:

Versatile engineering plastics such as polypropylene resin (PP),polyethylene resin (PE), polyacetal resin (POM), polyvinyl chlorideresin (PVC), polyamide resin (PA), acrylonitrile butadiene styrene resin(ABS), polylactide resin (PLA), polyphenylene sulfide resin (PPS),polyether ether ketone (PEEK), polycarbonate (PC), modifiedpolyphenylene ether, polybutylene terephthalate, and polyethyleneterephthalate, and engineering plastics such as polysulfone,polyethersulfone, polyphenylene sulfide, polyacrylate, polyimide,polyamide imide, polyether imide, and polyether ether ketone

An additive such as a pigment, metal, ceramic, wax, flame retardant,antioxidant, or thermal stabilizer may be mixed into the thermoplasticmaterial. In the plasticizing device 90, the thermoplastic material isplasticized by the rotation of the flat screw 40 and the heating by theheater 58 and thus transformed into a molten state. The shaping materialthus produced hardens due to a temperature drop after being ejected fromthe nozzle hole 61.

It is desirable that the thermoplastic material is heated to its glasstransition temperature or more and is ejected in a completely moltenstate from the nozzle hole 61. For example, it is desirable that the ABSresin, which has a glass transition temperature of approximately 120°C., is at approximately 200° C. when ejected from the nozzle hole 61. Inorder to eject the shaping material in such a high-temperature state, aheater may be provided around the nozzle hole 61.

In the ejection unit 200, for example, the following metal material maybe used as the main material, instead of the above thermoplasticmaterial. In this case, it is desirable that a component which meltswhen producing the shaping material is mixed with a powder materialformed of the following metal material in a powder state and that themixture is put into the plasticizing device 90.

Examples of Metal Material:

A single metal of magnesium (Mg), iron (Fe), cobalt (Co), chromium (Cr),aluminum (Al), titanium (Ti), copper (Cu), or nickel (Ni), or an alloycontaining one or more of these metals

Examples of Alloy:

Maraging steel, stainless steel, cobalt-chromium-molybdenum, titaniumalloy, nickel alloy, aluminum alloy, cobalt alloy, and cobalt-chromiumalloy

In the ejection unit 200, a ceramic material can be used as the mainmaterial, instead of the above metal material. As the ceramic material,for example, an oxide ceramic such as silicon dioxide, titanium dioxide,aluminum oxide or zirconium oxide, or a non-oxide ceramic such asaluminum nitride can be used. When a metal material or ceramic materialas described is used as the main material, the shaping material arrangedat the shaping table 310 may be hardened, for example, by sintering withlaser irradiation, hot air, or the like.

The powder material of the metal material or the ceramic material putinto the material supply unit 20 may be a mixture material made up of aplurality of types of powder of a single metal, powder of an alloy, orpowder of a ceramic material mixed together. The powder material of themetal material or the ceramic material may be coated, for example, witha thermoplastic resin as described above or other thermoplastic resins.In this case, the thermoplastic material may be melted and thus manifestits fluidity in the plasticizing device 90.

To the powder material of the metal material or the ceramic material putinto the material supply unit 20, for example, the following solvent canbe added. As the solvent, one type or a combination of two or more typesselected from below can be used.

Examples of Solvent:

Water; (poly) alkylene glycol monoalkyl ethers such as ethylene glycolmonomethyl ether, ethylene glycol monoethyl ether, propylene glycolmonomethyl ether, and propylene glycol monoethyl ether; acetic esterssuch as ethyl acetate, n-propyl acetate, isopropyl acetate, n-butylacetate, and isobutyl acetate; aromatic hydrocarbons such as benzene,toluene, and xylene; ketones such as methyl ethyl ketone, acetone,methyl isobutyl ketone, ethyl n-butyl ketone, diisopropyl ketone, andacetyl acetone; alcohols such as ethanol, propanol, and butanol;tetraalkylammonium acetates; sulfoxide-based solvents such as dimethylsulfoxide and diethyl sulfoxide; pyridine-based solvents such aspyridine, y-picoline, and 2,6-lutidine; tetraalkylammonium acetate (forexample, tetrabutylammonium acetate or the like); and ionic liquid suchas butyl carbitol acetate, or the like.

Moreover, for example, the following binder can be added to the powdermaterial of the metal material or the ceramic material put into thematerial supply unit 20.

Examples of Binder:

Acrylic resin, epoxy resin, silicone resin, cellulose-based resin orother synthetic resins or PLA (polylactic acid), PA (polyamide), PPS(polyphenylene sulfide), PEEK (polyether ether ketone), or otherthermoplastic resins

B. Second Embodiment

FIG. 4 is an explanatory view showing a schematic configuration of athree-dimensional shaping device 100 b in a second embodiment. Thethree-dimensional shaping device 100 b in the second embodiment isdifferent from the first embodiment in that an ejection unit 200 b has afirst nozzle unit 60A and a second nozzle unit 60B. Also, in thethree-dimensional shaping device 100 b in the second embodiment, theconfiguration of a plasticizing unit 30 b of a plasticizing device 90 bis different from that in the first embodiment. The other configurationsare the same as in the first embodiment shown in FIG. 1 unless statedotherwise.

In the first nozzle unit 60A, a first nozzle flow path 62A and a firstnozzle hole 61A are provided. The first nozzle hole 61A is a part thatis provided at an end part at the side communicating with the atmosphereand that has a reduced flow path cross section, in the first nozzle unit60A. The first nozzle flow path 62A is supplied with the shapingmaterial from the plasticizing device 90 b via a flow rate adjustmentmechanism 70 b. The shaping material supplied to the first nozzle flowpath 62A is ejected from the first nozzle hole 61A. In this embodiment,the diameter of the first nozzle flow path 62A is the same as thediameter of a first communication hole 55A. However, the diameter of thefirst nozzle flow path 62A may be smaller than the diameter of the firstcommunication hole 55A. A nozzle diameter Dnl of the first nozzle hole61A is smaller than the diameter of the first nozzle flow path 62A.

In the second nozzle unit 60B, a second nozzle flow path 62B and asecond nozzle hole 61B are provided. The second nozzle hole 61B is apart that is provided at an end part at the side communicating with theatmosphere and that has a reduced flow path cross section, in the secondnozzle unit 60B. The second nozzle flow path 62B is supplied with theshaping material from the plasticizing device 90 b via the flow rateadjustment mechanism 70 b. The shaping material supplied to the secondnozzle flow path 62B is ejected from the second nozzle hole 61B. In thisembodiment, the diameter of the second nozzle flow path 62B is the sameas the diameter of a second communication hole 55B. However, thediameter of the second nozzle flow path 62B may be smaller than thediameter of the second communication hole 55B. A nozzle diameter Dn2 ofthe second nozzle hole 61B is smaller than the diameter of the secondnozzle flow path 62B.

In this embodiment, the nozzle diameter Dnl of the first nozzle hole 61Ais smaller than the nozzle diameter Dn2 of the second nozzle hole 61B. Anozzle length Ln1 of the first nozzle hole 61A is the same as a nozzlelength Ln2 of the second nozzle hole 61B. The nozzle lengths Ln1, Ln2are the flow path length from the end part at the side of theplasticizing device 90 b to the end part at the side communicating withthe atmosphere, in the nozzle holes 61A, 61B.

In this embodiment, the first communication hole 55A, the secondcommunication hole 55B, a spiral first groove part 56A coupled to thefirst communication hole 55A, and a spiral second groove part 56Bcoupled to the second communication hole 55B are formed at the bottomsurface 51 of a barrel 50 b in the plasticizing unit 30 b. The firstcommunication hole 55A communicates with the first nozzle hole 61A. Thesecond communication hole 55B communicates with the second nozzle hole61B. The detailed shape of the barrel 50 b in this embodiment will bedescribed later with reference to FIG. 5.

In the flow rate adjustment mechanism 70 b, a first valve mechanism 71Aand a second valve mechanism 71B are provided. Each of the first valvemechanism 71A and the second valve mechanism 71B in this embodiment isformed of a butterfly valve. The first valve mechanism 71A opens andcloses under the control of the control unit 500 and switches betweencommunication and non-communication between the first communication hole55A and the first nozzle hole 61A. The second valve mechanism 71B opensand closes under the control of the control unit 500 and switchesbetween communication and non-communication between the secondcommunication hole 55B and the second nozzle hole 61B.

FIG. 5 is a top view showing the configuration of the bottom surface 51of the barrel 50 b in the second embodiment. In this embodiment, thefirst communication hole 55A, the second communication hole 55B, thefirst groove part 56A coupled to the first communication hole 55A, andthe second groove part 56B coupled to the second communication hole 55Bare provided, as described above. In FIG. 5, the first groove part 56Aand the second groove part 56B are hatched in order to facilitateunderstanding of the technology.

The first groove part 56A has a first center part 151A, a first spiralpart 152A, and a first material inflow part 153A. The first center part151A is a circular depression around the first communication hole 55A.One end of the first spiral part 152A is coupled to the firstcommunication hole 55A via the first center part 151A. The first spiralpart 152A spirally extends about the first center part 151A in such away as to form an arc toward the outer circumference of the bottomsurface 51. The other end of the first spiral part 152A is coupled tothe first material inflow part 153A. The first material inflow part 153Ais a groove-like part provided at the outer circumferential edge of thebottom surface 51 and wider than the first spiral part 152A. In thisembodiment, a first supply port 25A is arranged at the slope part 53above the first material inflow part 153A. The material supply unit 20and the first supply port 25A are coupled together via a first supplypath 22A.

The second groove part 56B has a second center part 151B, a secondspiral part 152B, and a second material inflow part 153B. The secondcenter part 151B is a circular depression around the secondcommunication hole 55B. One end of the second spiral part 152B iscoupled to the second communication hole 55B via the second center part151B. The second spiral part 152B spirally extends about the secondcenter part 151B in such a way as to form an arc toward the outercircumference of the bottom surface 51. In this embodiment, the lengthalong the spiral of the first spiral part 152A and the length along thespiral of the second spiral part 152B are the same. The second materialinflow part 153B is a groove-like part provided at the outercircumferential edge of the bottom surface 51 and wider than the secondspiral part 152B. In this embodiment, a second supply port 25B isarranged at the slope part 53 above the second material inflow part153B. The material supply unit 20 and the second supply port 25B arecoupled together via a second supply path 22B.

FIG. 6 is a cross-sectional view taken along VI-VI of the barrel 50 bshown in FIG. 5. In this embodiment, the shape of the first spiral part152A and the shape of the second spiral part 152B are different fromeach other. Specifically, a width W1 of the first spiral part 152A isnarrower than the width W2 of the second spiral part 152B. A depth H1 ofthe first spiral part 152A is the same as a depth H2 of the secondspiral part 152B. Therefore, a cross-sectional area A1 of the firstspiral part 152A is smaller than a cross-sectional area A2 of the secondspiral part 152B. In this embodiment, the cross-sectional area A1 of thefirst spiral part 152A is constant and the cross-sectional area A2 ofthe second spiral part 152B is constant.

In the configuration of the three-dimensional shaping device 100 bdescribed above, as the control unit 500 executes shaping processing toshape a three-dimensional shaped object, the material in the materialsupply unit 20 travels through the first supply path 22A and is suppliedfrom the first supply port 25A into the supply space 59 between thelateral surface 46 of the rotating flat screw 40 and the sidewallsurface 52. The material in the material supply unit 20 also travelsthrough the second supply path 22B and is supplied from the secondsupply port 25B into the supply space 59 between the lateral surface 46of the rotating flat screw 40 and the sidewall surface 52.

In this embodiment, a part of the material supplied into the supplyspace 59 from the first supply port 25A travels between the blade parts43 of the flat screw 40 and flows into the first material inflow part153A provided below the first supply port 25A. The material not flowinginto the first material inflow part 153A and remaining in the supplyspace 59 is transported to the second material inflow part 153B by theblade parts 43 of the rotating flat screw 40 and flows into the secondmaterial inflow part 153B. The material not flowing into the secondmaterial inflow part 153B and remaining in the supply space 59 istransported again to the first material inflow part 153A by the bladeparts 43 of the rotating flat screw 40 and flows into the first materialinflow part 153A.

A part of the material supplied into the supply space 59 from the secondsupply port 25B travels between the blade parts 43 of the flat screw 40and flows into the second material inflow part 153B provided below thesecond supply port 25B. The material not flowing into the secondmaterial inflow part 153B and remaining in the supply space 59 istransported to the first material inflow part 153A by the blade parts 43of the rotating flat screw 40 and flows into the first material inflowpart 153A. The material not flowing into the first material inflow part153A and remaining in the supply space 59 is transported again to thesecond material inflow part 153B by the blade parts 43 of the rotatingflat screw 40 and flows into the second material inflow part 153B.

The material flowing into the first material inflow part 153A istransported into the first spiral part 152A by the rotation of the flatscrew 40. The material transported into the first spiral part 152A is atleast partly melted by the rotation of the flat screw 40 and the heatingby the heater 58 built inside the barrel 50 b, and thus becomes a fluidpaste-like shaping material. The shaping material is transported withinthe first spiral part 152A and pressure-fed into the first communicationhole 55A by the rotation of the flat screw 40.

The material flowing into the second material inflow part 153B istransported into the second spiral part 152B by the rotation of the flatscrew 40. The material transported into the second spiral part 152B isat least partly melted by the rotation of the flat screw 40 and theheating by the heater 58 built inside the barrel 50 b, and thus becomesa fluid paste-like shaping material. The shaping material is transportedwithin the second spiral part 152B and pressure-fed into the secondcommunication hole 55B by the rotation of the flat screw 40.

In this embodiment, to shape the outer shape of the three-dimensionalshaped object that needs a higher dimensional accuracy than the innershape, the control unit 500 causes the second valve mechanism 71B toclose and the first valve mechanism 71A to open and thus causes theshaping material to be ejected from the first nozzle hole 61A with thesmaller diameter toward the top of the shaping table 310, therebyshaping the three-dimensional shaped object. The outer shape refers to asite visible from outside, of the three-dimensional shaped object. Theinner shape refers to a site of the three-dimensional shaped objectother than the outer shape. Meanwhile, to shape the inner shape of thethree-dimensional shaped object, the control unit 500 causes the firstvalve mechanism 71A to close and the second valve mechanism 71B to openand thus causes the shaping material to be ejected from the secondnozzle hole 61B with the larger diameter toward the top of the shapingtable 310, thereby shaping the three-dimensional shaped object.

In the three-dimensional shaping device 100 b in this embodimentdescribed above, the material is plasticized by the pair of the flatscrew 40 and the barrel 50 b and the shaping material can be ejectedfrom the first communication hole 55A and the second communication hole55B. Therefore, the shaping material can be supplied to the first nozzleunit 60A and the second nozzle unit 60B without complicating theconfiguration of the three-dimensional shaping device 100 b having theplasticizing device 90 b incorporated therein.

Also, in this embodiment, the first groove part 56A formed in the barrel50 b has the first spiral part 152A, and the second groove part 56B hasthe second spiral part 152B. Therefore, the material can be melted inthe first groove part 56A and transported toward the first communicationhole 55A more easily by the rotation of the flat screw 40. Also, thematerial can be melted in the second groove part 56B and transportedtoward the second communication hole 55B more easily by the rotation ofthe flat screw 40.

Also, in this embodiment, since the shape of the first spiral part 152Aand the shape of the second spiral part 152B are different from eachother, the shaping material can be ejected from the first communicationhole 55A and the second communication hole 55B at different flow ratesand with different pressures. Particularly, in this embodiment, thecross-sectional area A1 of the first spiral part 152A communicating withthe first communication hole 55A is smaller than the cross-sectionalarea A2 of the second spiral part 152B communicating with the secondcommunication hole 55B. Therefore, the pressure of the shaping materialpressure-fed into the first communication hole 55A communicating withthe first nozzle hole 61A with the smaller diameter can be made higherthan the pressure of the shaping material pressure-fed into the secondcommunication hole 55B communicating with the second nozzle hole 61Bwith the larger diameter. Thus, a drop in the amount of the shapingmaterial ejected from the first nozzle hole 61A having a higherresistance than the second nozzle hole 61B can be restrained.

Also, in this embodiment, the blade part 43 can stir the material in theflat screw 40 and the barrel 50 b. This enables the material to floweasily into the first material inflow part 153A and the second materialinflow part 153B.

Also, in this embodiment, the nozzle diameter Dnl of the first nozzlehole 61A is smaller than the nozzle diameter Dn2 of the second nozzlehole 61B. Therefore, the outer shape, which needs higher quality interms of dimensional accuracy and surface roughness than the inner shapeof the three-dimensional shaped object, can be finely shaped by ejectingthe shaping material from the first nozzle hole 61A with the smallerdiameter. Also, the inner shape of the three-dimensional shaped objectcan be shaped in a short time by ejecting the shaping material from thesecond nozzle hole 61B with the larger diameter.

Also, in this embodiment, the first valve mechanism 71A can switch onand off the ejection of the shaping material from the first nozzle hole61A, and the second valve mechanism 71B can switch on and off theejection of the shaping material from the second nozzle hole 61B.Therefore, when the shaping material is ejected from the first nozzlehole 61A to shape a three-dimensional shaped object, the shapingmaterial can be restrained from leaking from the second nozzle hole 61B.When the shaping material is ejected from the second nozzle hole 61B toshape a three-dimensional shaped object, the shaping material can berestrained from leaking from the first nozzle hole 61A.

Also, in this embodiment, the first supply port 25A is arranged at theslope part 53 above the first material inflow part 153A, and the secondsupply port 25B is arranged at the slope part 53 above the secondmaterial inflow part 153B. This enables the material to be supplied intothe supply space 59 from a position near each material inflow part 153A,153B and therefore enables the material to flow into each materialinflow part 153A, 153B more easily.

C. Third Embodiment

FIG. 7 is a top view showing the configuration of the bottom surface 51of a barrel 50 c in a third embodiment. In a three-dimensional shapingdevice 100 c in the third embodiment, the configuration of the barrel 50c in an ejection unit 200 c is different from that in the secondembodiment. Specifically, a first communication hole 55A, a secondcommunication hole 55B, a third communication hole 55C, and a fourthcommunication hole 55D communicating respectively with separate nozzleholes 61 are formed at the bottom surface 51 of the barrel 50 c. Also, afirst groove part 56A coupled to the first communication hole 55A, asecond groove part 56B coupled to the second communication hole 55B, athird groove part 56C coupled to the third communication hole 55C, and afourth groove part 56D coupled to the fourth communication hole 55D areformed at the bottom surface 51 of the barrel 50 c. A first supply port25A supplying the material to the first groove part 56A, a second supplyport 25B supplying the material to the second groove part 56B, a thirdsupply port 25C supplying the material to the third groove part 56C, anda fourth supply port 25D supplying the material to the fourth groovepart 56D are formed at a part forming the sidewall surface 52 of thebarrel 50 c. The other configurations are the same as in the secondembodiment unless stated otherwise. In FIG. 7, the groove parts 56A,56B, 56C, 56D are hatched in order to facilitate understanding of thetechnology.

The first groove part 56A has a first center part 151A, a first spiralpart 152A, and a first material inflow part 153A. The first center part151A is a circular depression around the first communication hole 55A.One end of the first spiral part 152A is coupled to the firstcommunication hole 55A via the first center part 151A. The first spiralpart 152A spirally extends about the first center part 151A in such away as to form an arc toward the outer circumference of the bottomsurface 51. The other end of the first spiral part 152A is coupled tothe first material inflow part 153A. The first material inflow part 153Ais a groove-like part provided at the outer circumferential edge of thebottom surface 51 and wider than the first spiral part 152A. The firstsupply port 25A is arranged at the slope part 53 above the firstmaterial inflow part 153A.

The second groove part 56B has a second center part 151B, a secondspiral part 152B, and a second material inflow part 153B. The secondgroove part 56B has the shape of the first groove part 56A rotatedclockwise by 90 degrees about the center of the bottom surface 51. Thesecond supply port 25B communicating with the material supply unit 20 isarranged at the slope part 53 above the second material inflow part153B.

The third groove part 56C has a third center part 151C, a third spiralpart 152C, and a third material inflow part 153C. The third groove part56C has the shape of the second groove part 56B rotated clockwise by 90degrees about the center of the bottom surface 51. The third supply port25C communicating with the material supply unit 20 is arranged at theslope part 53 above the third material inflow part 153C.

The fourth groove part 56D has a fourth center part 151D, a fourthspiral part 152D, and a fourth material inflow part 153D. The fourthgroove part 56D has the shape of the third groove part 56C rotatedclockwise by 90 degrees about the center of the bottom surface 51. Thefourth supply port 25D communicating with the material supply unit 20 isarranged at the slope part 53 above the fourth material inflow part153D.

In this embodiment, the material supply unit 20 and the respectivesupply ports 25A, 25B, 25C, 25D are coupled together via four supplypaths 22A, 22B, 22C, 22D. Also, four material supply units 20 may beprovided, and the respective supply ports 25A, 25B, 25C, 25D maycommunicate with the respective material supply units 20 via therespective supply paths 22A, 22B, 22C, 22D. For example, the firstsupply port 25A may communicate with a first material supply unit viathe first supply path 22A. The second supply port 25B may communicatewith a second material supply unit via the second supply path 22B. Thethird supply port 25C may communicate with a third material supply unitvia the third supply path 22C. The fourth supply port 25D maycommunicate with a fourth material supply unit via the fourth supplypath 22D. Different types of materials may be accommodated in therespective material supply units 20.

In the three-dimensional shaping device 100 c in this embodimentdescribed above, each supply port 25A, 25B, 25C, 25D is arranged at theslope part 53 above each material inflow part 153A, 153B, 153C, 153D.This enables the material to be supplied into the supply space 59 from aposition near each material inflow part 153A, 153B, 153C, 153D andtherefore enables the material to flow into each material inflow part153A, 153B, 153C, 153D more easily.

D. Other Embodiments

(D1) In the three-dimensional shaping devices 100, 100 b, 100 c in theabove embodiments, the blade part 43 of the flat screw 40 is providedparallel to the rotation axis RX. However, the blade part 43 may have asurface sloped with respect to the rotation axis RX. Specifically, thesurface of the blade part 43 at the front side in the direction ofrotation of the flat screw 40 may be sloped with respect to the rotationaxis RX in such a way that the material is pushed out toward the endsurface 45 when the material comes in contact with the surface at thefront side in the direction of rotation of the flat screw 40, of theblade part 43 of the rotating flat screw 40. In this case, the bladepart 43 of the rotating flat screw 40 can pressure-feed the materialbetween the flat screw 40 and the barrel 50 toward the bottom surface 51of the barrel 50. This can further facilitate the supply of the materialto the groove part 56.

(D2) In the three-dimensional shaping devices 100, 100 b, 100 c in theabove embodiments, the cross-sectional area of the spiral part 152 isconstant. However, the cross-sectional area of the spiral part 152 maybecome smaller as it goes toward the communication hole 55. For example,the spiral part 152 may be formed with a width decreasing as it goestoward the communication hole 55, or may be formed with a depthdecreasing as it goes toward the communication hole 55. In this case,the pressure of the shaping material pressure-fed into the communicationhole 55 from inside the spiral part 152 can be increased.

(D3) In the three-dimensional shaping devices 100, 100 b, 100 c in theabove embodiments, the flat screw 40 has the blade part 43. However, theflat screw 40 may not have the blade part 43. Even in this case, thematerial can be continuously supplied to the groove part 56.

(D4) In the three-dimensional shaping devices 100, 100 b, 100 c in theabove embodiments, the sidewall surface 52 has the slope part 53.However, the sidewall surface 52 may not have the slope part 53. Even inthis case, the material can be continuously supplied from the supplyspace 59 to the groove part 56.

(D5) In the three-dimensional shaping device 100 b in the above secondembodiment, the length Ln1 of the first nozzle hole 61A and the lengthLn2 of the second nozzle hole 61B are the same. However, the length Ln1of the first nozzle hole 61A and the length Ln2 of the second nozzlehole 61B may be different from each other. For example, the length Ln1of the first nozzle hole 61A may be longer than the length Ln2 of thesecond nozzle hole 61B.

(D6) FIG. 8 is an explanatory view showing a schematic configuration ofan injection molding device 110 as another form. An ejection unit 200dmay be used in the injection molding device 110 as well as in thethree-dimensional shaping devices 100, 100 b, 100 c. In the injectionmolding device 110 shown in FIG. 8, the ejection unit 200d has aninjection unit 600 in addition to the plasticizing device 90 and thenozzle unit 60. The configuration and functions of the plasticizingdevice 90 are as described above. In FIG. 8, the illustration of thematerial supply unit 20 and the supply path 22 is omitted. The injectionunit 600 measures the molten material supplied from the plasticizingdevice 90 and injects the material from the nozzle unit 60 into a spacedemarcated by an upper mold 710 and a lower mold, not illustrated, in amold-clamped state. The injection unit 600 has an injection cylinder610, an injection plunger 620, a check valve 630, and an injection motor640. As the injection motor 640 drives the injection plunger 620 toslide to the side opposite to the side of the communication hole 55, themolten material in the communication hole 55 is drawn into the injectioncylinder 610 and measured. As the injection motor 640 drives theinjection plunger 620 to slide toward the communication hole 55, themolten material in the injection cylinder 610 is pressure-fed toward thenozzle unit 60 and injected into the space demarcated by the upper mold710 and the lower mold.

E. Other Forms

The present disclosure is not limited to the foregoing embodiments andcan be implemented in various forms without departing from the spiritand scope of the present disclosure. For example, the present disclosurecan be implemented in the following forms. A technical feature in theembodiments corresponding to a technical feature in each of thefollowing forms can be replaced or combined with another according toneed, in order to solve apart or all of the problems in the presentdisclosure or in order to achieve a part or all of the effects of thepresent disclosure. Also, the technical feature can be deleted whereappropriate, unless described as essential in this specification.

(1) According to a first aspect of the present disclosure, aplasticizing device plasticizing a material into a molten material isprovided. The plasticizing device includes: a drive motor; a rotatingunit driven to rotate about a rotation axis by the drive motor andhaving an end surface perpendicular to the rotation axis and a lateralsurface intersecting with the end surface; a barrel having a bottomsurface facing the end surface of the rotating unit, and a heater; acase accommodating the rotating unit; and a material supply unitaccommodating the material. At least one of the barrel and the case hasa sidewall surface facing the lateral surface of the rotating unit andstanding up along an outer circumference of the bottom surface of thebarrel. At the bottom surface of the barrel, a communication holethrough which the molten material flows out and a spiral groove partcoupled to the communication hole are formed. The lateral surface of therotating unit and the sidewall surface together define a supply spacewhere the material is supplied from the material supply unit to thegroove part.

In the plasticizing device of this configuration, the material can becontinuously supplied to the groove part. Therefore, a change in thepressure of the molten material pressure-fed into the communication holecan be restrained. Thus, a change in the flow rate of the moltenmaterial ejected from the communication hole can be restrained.

(2) In the plasticizing device according to the above aspect, thesidewall surface may have a supply port through which the materialsupply unit and the supply space communicate with each other. Thematerial may travel through the supply port and flow into the supplyspace.

In the plasticizing device of this configuration, the material can besupplied from a position near the groove part. This can facilitate thesupply of the material to the groove part.

(3) In the plasticizing device according to the above aspect, therotating unit may have a plurality of plate-like blade parts protrudingfrom the lateral surface toward the supply space. The material maytravel between the blade parts and flow into the groove part.

In the plasticizing device of this configuration, the blade parts of therotating unit that is rotating can stir the material between therotating unit and the barrel. Therefore, the material can be retrainedfrom adhering to the barrel and closing the space between the rotatingunit and the barrel.

(4) In the plasticizing device according to the above aspect, the bladeparts may have a surface sloped along the rotation axis.

In the plasticizing device of this configuration, the blade parts canpressure-feed the material between the rotating unit and the barrel tothe bottom surface of the barrel. This can facilitate the supply of thematerial to the groove part.

(5) In the plasticizing device according to the above aspect, thesidewall surface may have, at a position intersecting with the bottomsurface, a slope part sloped in such a way as to approach a center ofthe bottom surface as it goes toward the bottom surface.

In the plasticizing device of this configuration, a flow of the materialalong the slope part toward the groove part can be formed. This canfacilitate the supply of the material to the groove part.

(6) In the plasticizing device according to the above aspect, the groovepart maybe reduced in cross-sectional area as it goes toward thecommunication hole.

In the plasticizing device of this configuration, the pressure of themolten material pressure-fed from inside the groove part into thecommunication hole can be increased.

(7) According to a second aspect of the present disclosure, athree-dimensional shaping device is provided. The three-dimensionalshaping device includes: a nozzle ejecting a shaping material; aplasticizing device plasticizing a material into the shaping materialand supplying the shaping material to the nozzle; and a control unitcontrolling the plasticizing device. The plasticizing device includes: adrive motor; a rotating unit driven to rotate about a rotation axis bythe drive motor and having an end surface perpendicular to the rotationaxis and a lateral surface intersecting with the end surface; a barrelhaving a bottom surface facing the end surface of the rotating unit, anda heater; a case accommodating the rotating unit; and a material supplyunit accommodating the material. At least one of the barrel and the casehas a sidewall surface facing the lateral surface of the rotating unitand standing up along an outer circumference of the bottom surface ofthe barrel. At the bottom surface of the barrel, a communication holethrough which the shaping material flows out into the nozzle and aspiral groove part coupled to the communication hole are formed. Thelateral surface of the rotating unit and the sidewall surface togetherdefine a supply space where the material is supplied from the materialsupply unit to the groove part.

In the three-dimensional shaping device of this configuration, thematerial can be continuously supplied to the groove part. Therefore, achange in the pressure of the shaping material pressure-fed into thecommunication hole can be restrained. Thus, a change in the flow rate ofthe shaping material ejected from the communication hole can berestrained.

The present disclosure can be implemented in various forms other thanthe plasticizing device. For example, the present disclosure can beimplemented as a three-dimensional shaping device, an ejection unit, andthe like.

What is claimed is:
 1. A plasticizing device plasticizing a materialinto a molten material, the plasticizing device comprising: a drivemotor; a rotating unit driven to rotate about a rotation axis by thedrive motor and having an end surface perpendicular to the rotation axisand a lateral surface intersecting with the end surface; a barrel havinga bottom surface facing the end surface of the rotating unit, and aheater; a case accommodating the rotating unit; and a material supplyunit accommodating the material, wherein at least one of the barrel andthe case has a sidewall surface facing the lateral surface of therotating unit and standing up along an outer circumference of the bottomsurface of the barrel, at the bottom surface of the barrel, acommunication hole through which the molten material flows out and aspiral groove part coupled to the communication hole are formed, and thelateral surface of the rotating unit and the sidewall surface togetherdefine a supply space where the material is supplied from the materialsupply unit to the groove part.
 2. The plasticizing device according toclaim 1, wherein the sidewall surface has a supply port though which thematerial supply unit and the supply space communicate with each other,and the material travels through the supply port and flows into thesupply space.
 3. The plasticizing device according to claim 1, whereinthe rotating unit has a plurality of plate-like blade parts protrudingfrom the lateral surface toward the supply space, and the materialtravels between the blade parts and flows into the groove part.
 4. Theplasticizing device according to claim 3, wherein the blade parts have asurface sloped along the rotation axis.
 5. The plasticizing deviceaccording to claim 1, wherein the sidewall surface has, at a positionintersecting with the bottom surface, a slope part sloped in such a wayas to approach a center of the bottom surface as it goes toward thebottom surface.
 6. The plasticizing device according to claim 1, whereinthe groove part is reduced in cross-sectional area as it goes toward thecommunication hole.
 7. A three-dimensional shaping device comprising: anozzle ejecting a shaping material; a plasticizing device plasticizing amaterial into the shaping material and supplying the shaping material tothe nozzle; and a control unit controlling the plasticizing device, theplasticizing device comprising: a drive motor; a rotating unit driven torotate about a rotation axis by the drive motor and having an endsurface perpendicular to the rotation axis and a lateral surfaceintersecting with the end surface; a barrel having a bottom surfacefacing the end surface of the rotating unit, and a heater; a caseaccommodating the rotating unit; and a material supply unitaccommodating the material, wherein at least one of the barrel and thecase has a sidewall surface facing the lateral surface of the rotatingunit and standing up along an outer circumference of the bottom surfaceof the barrel, at the bottom surface of the barrel, a communication holethrough which the shaping material flows out into the nozzle and aspiral groove part coupled to the communication hole are formed, and thelateral surface of the rotating unit and the sidewall surface togetherdefine a supply space where the material is supplied from the materialsupply unit to the groove part.